Hydrangeas that return from the crown "on a regular basis" every year but do not bloom usually have a problem with winter and require winter protection. Hydrangeas whose stems do not die off and who do not bloom may have a problem anytime from the point that flower buds are created until the time that the blooms are about to open. The flower can get killed by early frosts if the plant does not go dormant due to high nitrogen levels in the soil. The flower buds can also get killed later on if it gets too cold. And the flower buds can be eaten in the Spring by deer/rabbits/squirrels.
This hydrangea develops flower buds starting in July 2015 down in the South and August 2015 in the North. The buds will remain invisible until they open in the Spring 2016.
Usually Mariessi Variegated starts to have problem in the northern regions (Zones 5 and 6). This not only kills the Fall flower buds but, sometimes, it can kill the stems too, which start to regrow from the crown in Spring but then do not produce bloomage until the following year.
I actually like Mariessi Variegated for its leaves only. It does not produce as many blooms as other lacecaps and the blooms are not as striking as the variegated leaves (at least, not to me). Maybe there is something weird going on when hydrangeas have unusual foliage because I also had the same feelings towards Sun Goddess, a lacecap hydrangea that has yellow leaves and had pink blooms in my alkaline soil.
By the way, what zone/state/city are you in?
In the meantime, you can take these steps... Fertilize in Spring. Your last fertilization of any type should be no later than the end of June yearly in order to make sure that the plant goes dormant at the proper time. But fertilize again in July-August-September if you are in Florida or South Texas). Keep the soil as evenly moist as you can. That is important to do from July thru Winter and Spring if you are having bloomage issues. If the plant starts to dry out a lot, the flower buds will be the first thing to get zapped by the shrub. Mulch 3-4" to protect the roots and to maintain the soil moist for longer periods of time. Re-check mulch levels in the Fall. Do not forget to water in dry winters if you winter is dry and the soil has not frozen where you live in winter. To winter protect as the plant goes dormant, you can make a cage of chicken wire around the shrubs or around each shrub if they are not beside each other. There should more than 2" between the end of the stems and the chicken wire (blooms develop usually near the end of the stems). Pile on dead Fall leaves or use mulch to provide protection from winter. Put a cardboard on top and use something to hold it in place (rocks, etc). Leftover leaves should be added during the middle of winter as leaves settle so, re-ck to see if you need to add more in 2016. Remove the winter protection approximately 2 weeks after your average date of last frost where you live (nurseries can tell you this if you do not know). When Spring 2016 arrives or before, get the soil checked for NPK Levels.
You can do a formal soil test or get a cheapo soil test kit usually sold at plant nurseries or available by mail. If nitrogen levels are high, use low nitrogen fertilizers. Examples of good Spring fertilizers for "new" hydrangeas are organic compost, compsted manure and cottonseed meal (about 1/2 to 1 cup of any of those three). That is for the whole year provided you are not located in the extreme South, where an extra dose may be useful in July-August-ish if the shrubs go dormant on or after December. If phosphorus level are low, try using a high phosphorus fertilizer. Phosphorus is good for roots and blooms. Bone meal would be a good choice for this.
If you are going to replant, look for a location that provides dappled sun or morning sun & after shade. Down here in Texas, I look for a place on the east side of trees and walls that, during the summer, gets shade starting at 11am to 12pm. Also, make sure you can provide water there as well. Dig the new hole first. Water the plant the night before. And move as much of the rootball as you can. If necessary, use help to transport the shrub such the root ball does not collapse. The root system should not be large. The roots near the top 4" are used mostly to absorb water so try not to step on them or damage them (much). Moving the plants once the shrub is dormant is the best time; if you are here in the South, do not even think of transplanting now.
Luis
Oh, I just saw where you said you were in NC... I thought NC was a typo. Ha! Never mind...
